Live bolts for safe doors are normally operated by a crank assembly turned by a handle. Since it is best to space the live bolts uniformly around the safe door and not crowd them too close to the opening edge of the door, the crank assembly for the live bolts is preferably located in a mid-region of the door. This also locates the operating handle in the mid-region of the door where the space left for interaction with a combination lock is restricted.
Such spacial limitations, along with manufacturing tolerance problems of conventional live bolt locks, led us to an improved mechanism that not only solves these problems, but also works better and costs less. We have refined this for simplicity, operating effectiveness and reliability at a low cost in our improved live bolt mechanism.